The present invention relates to an electronic parts mounting apparatus for mounting electronic parts on a circuit board.
Recently, as electronic circuit boards become more and more highly dense and functional, and integrated electronic parts become larger and larger in size, high accuracy is demanded for an electronic parts mounting apparatus. Thus, it becomes necessary to mount the electronic parts on the electronic circuit board by accurately recognizing them and correcting their positions. In this case, since a visual field size is selected for a recognition camera from required mounting accuracy, divisional recognition means is employed to recognize an electronic part larger than the visual field size.
Now, explanation is given on an example of operation for recognizing an electronic part in an electronic parts mounting apparatus with reference to the drawings.
FIG. 9(a) shows a relationship between a visual field 10 of a recognition camera, an electronic part 2, and a nozzle 1 for holding the electronic part 2. When the electronic part 2 is smaller than the visual field of camera 10, as shown, the electronic part 2 can be recognized by aligning the position of the nozzle 1 at the center of visual field.
FIG. 9(b) shows a case where the electronic part 2 is larger than the visual field of camera 10. In this case, to recognize the electronic part 2, it is necessary to perform divisional recognition by varying the relative positional relationship between the nozzle 1 and the visual field of camera 10 as indicated by arrow.
As described, it is necessary to perform the divisional recognition to recognize the electronic part 2 larger than the visual field of camera 10. However, to vary the relative positional relationship between the nozzle 1 and the visual field of camera 10, it should be arranged that the nozzle 1 or the camera (visual field 10) can freely move on a plane opposite to the electronic part 2. Thus, there is a problem that the divisional recognition of the electronic part cannot be performed on an electronic parts mounting apparatus on which the relative positional relationship between the nozzle 1 and the camera cannot be varied.
In addition, the method performing divisional recognition by varying the relative positional relationship between the nozzle 1 and the visual field of camera 10 has a problem that it takes more time than the method performing recognition with a single visual field because the former captures images a plurality of times.
The present invention is intended to provide an electronic parts mounting apparatus which enables it to perform divisional recognition of an electronic part even when a relative positional relationship between a nozzle and a camera is not varied, and which can use the divisional recognition and single visual field recognition in combination, so that recognition is performed in a single visual field for an electronic part which can be recognized in a single visual field, enabling the time of recognition to be shortened.
To attain the above object, the electronic parts mounting apparatus of the present invention comprises a nozzle for holding an electronic part, a rotary driving member for rotating and driving the nozzle in a desired angle, a recognition camera for imaging the electronic part held by the nozzle, and part recognition means for changing a plurality of times the posture of the electronic part held by the nozzle with the rotary driving member when the center of the visual field of the recognition camera is positioned at a position different from the center of rotation of the nozzle, and recognizing the electronic part from partial recognition images obtained from the recognition camera every time the posture is changed.
According to the present invention, it is possible to obtain an electronic parts mounting apparatus enabling it to perform divisional recognition of an electronic part even when the relative positional relationship between the nozzle and the camera is not varied.
An electronic parts mounting apparatus according to a first aspect of the present invention comprises a nozzle for holding an electronic part, a rotary driving member for rotating and driving the nozzle in a desired angle, a recognition camera for imaging the electronic part held by the nozzle, and part recognition means for changing a plurality of times the posture of the electronic part held by the nozzle with the rotary driving member when the center of the visual field of the recognition camera is positioned at a position different from the center of rotation of the nozzle, and recognizing the electronic part from partial recognition images obtained from the recognition camera every time the posture is changed.
Thus, there is an advantage that even an electronic parts mounting apparatus arranged not to be capable of varying the positional relationship between the recognition camera and the electronic part to be recognized can recognize the contour of the electronic part by changing the posture of the electronic part a plurality of times with the rotary driving member, and capturing a partial image every time the posture is changed to recognize the contour of the electronic part.
An electronic parts mounting apparatus according to a second aspect of the present invention comprises a nozzle for holding an electronic part, a rotary driving member for rotating and driving the nozzle in a desired angle, a first recognition camera positioned with the center of its visual field at a position coincident with the center of rotation of the nozzle, and for imaging the electronic part held by the nozzle, a second recognition camera positioned with the center of its visual field at a position different from the center of rotation of the nozzle, and for imaging the electronic part held by the nozzle, and part recognition means, when recognizing an electronic part smaller than the visual field size of the camera, for batch recognizing the electronic part from a recognized image of the electronic part obtained from the first recognition camera, and, when recognizing an electronic part larger than the visual field size of the camera, for changing a plurality of times the posture of the electronic part held by the nozzle with the rotary driving member, and recognizing the electronic part from partial recognized images obtained from the second camera every time the posture is changed.
As the first recognition camera the center of visual field of which aligns the center of rotation of the nozzle is used for a small electronic parts which can be recognized with a single visual field, and the second recognition camera the center of visual field of which differs from the center of rotation of the nozzle is used for a large electronic part, there is provided an advantage that batch recognition and divisional recognition can be used in combination for recognizing an electronic part without varying the relative positional relationship between the nozzle and the first and second recognition cameras, so that time for recognition can be shortened.
An electronic parts mounting apparatus according to a third aspect of the present invention a nozzle for holding an electronic part, a rotary driving member for rotating and driving the nozzle in a desired angle, a recognition camera for imaging the electronic part held by the nozzle, a driving mechanism for varying the relative positional relationship between the center of visual field of the recognition camera and the center of rotation of the nozzle, and part recognition means, when recognizing an electronic part smaller than the visual field size of camera, for batch recognizing the electronic part from a recognized image of the electronic part obtained from the recognition camera by aligning the center of visual field of the recognition camera with the center of rotation of the nozzle with the driving mechanism, and, when recognizing an electronic part larger than the visual field size of the camera, for changing a plurality of times the posture of the electronic part held by the nozzle with the rotary driving member, and recognizing the electronic part from partial recognized images of the electronic part obtained from the camera every time the posture is changed.
There is provided an advantage that batch recognition and divisional recognition can be used in combination for recognizing an electronic part by varying the relative positional relationship between the recognition camera and the electronic part with the driving mechanism, so that the time for recognition can be shortened.
An electronic parts mounting apparatus according to a fourth aspect of the present invention is a one according to the third aspect of the present invention, wherein, when either one of the center of visual field of the recognition camera and the center of rotation of the nozzle is determined to be a reference for the driving mechanism, its driving direction is limited to one fixed direction.
This arrangements provide an advantage that the driving mechanism can be simplified.
An electronic parts mounting apparatus according to a fifth aspect of the present invention is one according to the third aspect of the present invention, further comprising calculation means for calculating a location for movement of the recognition camera from previously registered data on the center of rotation of the nozzle, the driving mechanism moving the recognition camera to the location for movement calculated by the calculation means.
There is provided an advantage that divisional recognition can be performed even when the center of rotation data of the nozzle is varied.
An electronic parts mounting apparatus according to a sixth aspect of the present invention is one according to the third aspect of the present invention, further comprising calculation means for calculating a location for movement of the recognition camera from previously registered sizes of electronic parts, the driving mechanism moving the recognition camera to the location for movement calculated by the calculation means.
There is provided an advantage that divisional recognition can be performed even when the outer size of an electronic part is varied.